Effect of applied magnetic field on the surface morphology, optical and electrical properties of tin oxide (SnO2) nanomaterial for meat spoilage detection
Date of Publication
2015
Document Type
Master's Thesis
Degree Name
Master of Science in Physics
Subject Categories
Physics
College
College of Science
Department/Unit
Physics
Thesis Adviser
Gil Nonato C. Santos
Defense Panel Chair
Emmanuel T. Rodulfo
Defense Panel Member
Christopher T. Que
Ivan B. Culaba
Abstract/Summary
The study examined the effect of applied magnetic field (AMF) on the surface morphology, elemental composition, optical, and electrical properties of tin oxide (SnO2) nanomaterials. Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) Analysis were used in morphology characterization. Photoluminescence characterization was also completed using Applied Spectral Imaging SD-300. The current voltage (IV) characteristics were determined using the Keithley 2400 Source Meter and Keithley 2010 multimeter, the result from which the resistivity of the sample was computed. The study also explored the gas sensing capability of the synthesized nanomaterials to meat spoilage.
The nanomaterials were produced using the Horizontal Vapor Phase Crystal Growth (HVPG) deposition method where fused quartz tubes containing 50 mg of SnO2 powder was evacuated to a base pressure of 10-6 Torr and annealed at a temperature of 1,200 ºC at growth time of 4 hours, 6 hours, and 8 hours with a ramp time of 40 minutes using a Thermolyne horizontal tube furnace. The magnetic field intensity was varied from 2500 gauss to 3100 gauss as well as the position of the permanent magnet along the tube.
In the absence of applied magnetic field (AMF), the diameters of the grown structures were found to increase with increase in growth time. With the presence of AMF, nanowire formation was favored with a more defined structure and greater density when the magnet is farther from the furnace, section 3b, and at greater intensity, 3100 gauss. A greater density of nanowire deposit at the mentioned section was also observed in longer growth time, 8 hours. On the other hand, lower magnetic field intensity, 2500 gauss, was observed to produce lower density and length of structures. The presence of the external magnetic field, along with the presence of temperature gradient, was found to be responsible for the formation of the homogenized nanowires. However, the temperature gradient has a greater influence than the presence of external magnetic field in the growth of the nanowire. EDX confirms the presence of tin oxide on the structures formed in the sections of the tube.
Abstract Format
html
Language
English
Format
Electronic
Accession Number
CDTG006545
Shelf Location
Archives, The Learning Commons, 12F Henry Sy Sr. Hall
Physical Description
1 computer optical disc ; 4 3/4 in.
Keywords
Magnetic fields; Stannic oxide; Nanostructured materials
Upload Full Text
wf_no
Recommended Citation
Briones, J. C. (2015). Effect of applied magnetic field on the surface morphology, optical and electrical properties of tin oxide (SnO2) nanomaterial for meat spoilage detection. Retrieved from https://animorepository.dlsu.edu.ph/etd_masteral/5048